Pascal Kesselmark on Twitter: "Once you use a calculator with Reverse Polish Notation, you can't go back… So happy I found an iOS app which emulates my 1990 HP 48SX. In the
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Reverse-engineering and simulating Sinclair's amazing 1974 calculator with half the ROM of the HP-35
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CAM #4 - Pt 2 What is RPN Reverse Polish Notation / How to use RPN on the HP 12C, HP 15C and HP 50g - YouTube
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